Calibration of the logarithmic-periodic dipole antenna (LPDA) radio stations at the Pierre Auger Observatory using an octocopter

SÁNCHEZ, F. (ET. AL, VER PUBLICACION ADJUNTA)

JOURNAL OF INSTRUMENTATION

IOP PUBLISHING LTD

Lugar: Londres; Año: 2017

1748-0221

An in-situ calibration of a logarithmic periodic dipole antenna with a frequency cover-age of 30 MHz to 80 MHz is performed. Such antennas are part of a radio station system used fordetection of cosmic ray induced air showers at the Engineering Radio Array of the Pierre AugerObservatory, the so-called Auger Engineering Radio Array (AERA). The directional and frequencycharacteristics of the broadband antenna are investigated using a remotely piloted aircraft carryinga small transmitting antenna. The antenna sensitivity is described by the vector effective lengthrelating the measured voltage with the electric-field components perpendicular to the incomingsignal direction. The horizontal and meridional components are determined with an overall un-+2.8certainty of 7.4 +0.9−0.3 % and 10.3 −1.7 % respectively. The measurement is used to correct a simulatedresponse of the frequency and directional response of the antenna. In addition, the influence of theground conductivity and permittivity on the antenna response is simulated. Both have a negligibleinfluence given the ground conditions measured at the detector site. The overall uncertainties ofthe vector effective length components result in an uncertainty of 8.8+2.1−1.3 % in the square root of theenergy fluence for incoming signal directions with zenith angles smaller than 60deg.